Update dummy_robot/dummy_map_server/README.md

Co-authored-by: Audrow Nash <[email protected]>
Signed-off-by: Bey Hao Yun <[email protected]>

dummy_robot/dummy_map_server/README.md

@@ -10,7 +10,7 @@ Please refer to [dummy_robot_bringup](https://github.com/ros2/demos/tree/rolling
 
 An occupancy grid can be thought of as a map of an environment that has been divided into grid cells, where each grid cell is either occupied or unoccupied (in advanced applications, they can have other states, too).
 
-This map of occupied and unoccupied grid cells can be used to help a robot navigate a space, for example to drive through a room with furnitures.
+This map of occupied and unoccupied grid cells can be used to help a robot navigate a space, for example to drive through a room with furniture.
 
 If a robot is navigating a new room, however, there may also be grid cells that are marked as unknown, until that area is explored.